1.What is cerebral angiography? Digital subtraction cerebral angiography (DSA) is an examination method that inserts an arterial catheter from the femoral artery and injects a contrast agent into the blood supplying arteries of the brain through the catheter to show vascular lesions in the brain and neck. Through this examination, it can understand and clarify whether there is stenosis and occlusion of intracranial and extracranial arteries, as well as the location and degree of stenosis and occlusion, and whether there is the establishment of collateral circulation; it can also confirm the diagnosis of intracranial aneurysms and vascular malformations, so as to take targeted treatment, which is the “gold standard” for the diagnosis of cerebrovascular disease and cannot be replaced by other examination methods. This technology is the “gold standard” for diagnosing cerebrovascular disease, which cannot be replaced by other examination methods. Which patients need cerebral angiography? All patients who may have cerebral artery stenosis should undergo cerebral angiography, including transient ischemic attack (TIA), watershed cerebral infarction, large cerebral infarction, youth stroke, cerebral artery steal syndrome, etc. Non-hypertensive cerebral hemorrhage, subarachnoid hemorrhage and other hemorrhagic cerebrovascular diseases should also do cerebral angiography to clarify the cause of bleeding. 3.What are the complications of cerebral angiography? At present, cerebral angiography is a very mature examination technique, which has been carried out in our department for many years, and the number of cases is close to one thousand. The complication rate is very low, around 0.5%, mainly occurring in the elderly, patients with severe hardening of blood vessels, which is easy to plaque detachment causing cerebral infarction. 4.What is interventional therapy for cerebrovascular disease? What kind of diseases can it treat? Interventional therapy of cerebrovascular disease refers to the new technology of diagnosing and treating the lesions of blood vessels in the brain, head and neck by using catheter technology. It includes stent implantation and arterial thrombolysis for ischemic cerebrovascular disease, as well as blockage and embolization for hemorrhagic cerebrovascular disease. Compared with craniotomy, interventional therapy has the advantages of no incision, small trauma, easy operation, reliable efficacy and safe treatment. Diseases that can be treated by interventional therapy include: 1) cerebral arteriovenous malformationfistula; 2) spinal arteriovenous malformation; 3) dural (spinal) meningeal arteriovenous fistula; 4) cavernous sinus fistula of internal carotid artery; 5) aneurysm; 6) acute cerebral infarction; 7) cerebral vasospasm; 8) cerebral vascular stenosis; and 9) preoperative embolization of cervical hemodynamically-rich tumors.